3D cell-laden hydrogels are increasingly used for in vitro and ex vivo cell expansion, controlled stem cell differentiation, and regenerative medicine. [1] Hydrogels can be fabricated by derivatives of purely synthetic polymers (e.g., poly(ethylene glycol) or PEG) and/or naturally derived biomacromolecules (e.g., gelatin, hyaluronic acid, or heparin). [2] Tumor basement membrane derived Matrigel is routinely used as a convenient matrix for 3D cell culture owing to its inherent cell affinity provided by laminin, collagen IV, and residual growth factors. However, Matrigel contains ill-defined and batch-to batch variability of extracellular matrix (ECM) components that may present challenges for studying the contributions of individual matrix cues on cell fate processes. To this end, synthetic PEG-based hydrogels afford a blank slate in which a bottom-up approach can be used to impart precise biochemical and biophysical properties in the cell-laden network. Advances in material chemistry have also enabled the conjugation of a variety of ECM motifs to the otherwise inert PEG-based network, as well as for spatiotemporal manipulation of matrix properties to facilitate the study of cell fate processes within a highly defined and controllable microenvironment. Chemically defined PEG-based hydrogels are particularly advantageous for studying iPSC behaviors in 3D. [3] For example, PEG hydrogels formed by Michael-type additions have proven effective in cell encapsulation owing to the reaction specificity between vinyl sulfone/maleimide (VS/MAL) and thiol (SH) moieties. Hubbell and colleagues utilized VS-SH reactions to determine the role of integrin activation on embryonic stem cell (ESC) self-renewal. [4] Lim et al. later use PEG-based VS-SH hydrogels for maintaining stemness of three human ESC lines. [5] Nonetheless, the reaction rates of Michael-type additions may be difficult to control and vary greatly from seconds to hours, depending on the type of Michael donor-acceptor pairs (e.g., VS-SH ≈ 30-120 min and MAL-SH ≈tens of seconds). [4a] Alternatively, enzymatic crosslinking provides excellent cytocompatibility and tunable gelation kinetics for in situ cell encapsulation. For instance, Xeno-free, chemically defined poly(ethylene glycol) (PEG)-based hydrogels are being increasingly used for in vitro culture and differentiation of human induced pluripotent stem cells (hiPSCs). These synthetic matrices provide tunable gelation and adaptable material properties crucial for guiding stem cell fate. Here, sequential norbornene-click chemistries are integrated to form synthetic, dynamically tunable PEG-peptide hydrogels for hiPSCs culture and differentiation. Specifically, hiPSCs are photoencapsulated in thiol-norbornene hydrogels crosslinked by multiarm PEG-norbornene (PEG-NB) and proteaselabile crosslinkers. These matrices are used to evaluate hiPSC growth under the influence of extracellular matrix properties. Tetrazine-norbornene (Tz-NB) click reaction is then employed to dynamically stiffen the cell-laden hydrogels. Fast ...

The antigen reactive with murine monoclonal antibody (MAb) KS1/4 is expressed on epithelial malignancies and some normal epithelial tissues. Studies were undertaken to evaluate KS1/4-methotrexate (KS1/4-MTX) immunoconjugate in patients with advanced non-small cell carcinoma of the lung. Eleven patients in two different groups received KS1/4-MTX in two different escalating dose infusion schedules with a maximal tolerated dose of 1,750 mg/M2 and a cumulative dose of MTX of 40 mg/M2. Toxicities were similar in both groups and included fever, anorexia, nausea, vomiting, diarrhea, abdominal pain, guaiac positive stool, and hypoalbuminemia. Two patients had an associated aseptic meningitis. One patient had a 50% decrease in two lung nodules without a change in lymphangitic infiltrates. This patient received a second course of treatment and developed an immune complex-mediated arthritis and serum sickness. Four patients mounted a human antimouse antibody response. Post-treatment tumor biopsies documented binding of MAb KS1/4. These studies document the feasibility and potential usefulness of a MAb directed against tumor-associated antigens with the targeting of chemotherapeutic drugs in patients with non-small cell lung carcinoma.

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Objective: A combined thyroid transcription factor 1 (TTF-1) and Napsin A double stain has been shown to be useful in the diagnosis of adenocarcinoma (ADC). This study compares differences in double staining patterns among vendor antibodies (Leica, Dako, and Biocare). Study Design: The cohorts included 35 FNA cell blocks of lung ADC and 24 cell blocks of lung squamous cell carcinoma (SqCCA). Double-staining immunohistochemistry was performed with TTF-1 as a brown nuclear stain and Napsin A as a red cytoplasmic stain, using three sets of double stains. Additionally, FISH expression was performed on SqCCAs with aberrant TTF-1 expression. Results: The sensitivity for the double stains ranged from 40 to 74%, while the specificity ranged from 88 to 96%. Two Leica TTF-1-positive SqCCAs also showed low-level amplification by FISH assay not seen in the TTF-1-negative control SqCCAs. Conclusion: The use of Dako TTF-1 antibody paired with Leica Napsin A antibody as a double stain yielded the best results for diagnosing ADC; additionally, the Leica Napsin A-only staining results had the highest positive predictive value at 97%. Both Dako and Biocare antibodies expressed less staining of SqCCAs than Leica staining.

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Splenectomy remains the preferred treatment for chronic immune thrombocytopenia (ITP) after corticosteroid failure, despite the risks of despite surgical complications and infection. The aim of this study was to assess the efficacy of and tolerance to rituximab through a retrospective analysis of 35 refractory/relapsing ITP patients treated from 2004 to 2013. The median age of subjects was 46 years (14-80). Rituximab was given at a weekly dose of 375 mg/m(2) for 4 weeks. Median time from diagnosis to first infusion was 17 months (1-362) and follow-up was 47 months (2-133). The overall response rates at 1 and 2 years after the first infusion were 47 and 38 %, with complete response rates of 24 and 25 %, respectively. Median duration of response was 38 months (1-123), with 37 % of patients maintaining a durable response (>1 year). Twenty-nine percent of patients had undergone splenectomy. A durable response after rituximab was more frequently observed in patients undergoing second-line therapy than those in third or later (83 versus 35 %, P = 0.01). Forty-four percent of patients experienced mild hypogammaglobulinaemia after rituximab, and no clinical infection occurred. To conclude, rituximab should be considered as an alternative treatment to splenectomy. Its efficacy and safety profile should lead us to choose this medical option therapy before surgery for ITP patients.

BackgroundThe majority of childhood deaths occur in low- and middle-income countries (LMICs). Many of these deaths are avoidable with basic critical care interventions. Quantifying the burden of pediatric critical illness in LMICs is essential for targeting interventions to reduce childhood mortality.ObjectiveTo determine the burden of hospitalization and mortality associated with acute pediatric critical illness in LMICs through a systematic review and meta-analysis of the literature.Data Sources and Search StrategyWe will identify eligible studies by searching MEDLINE, EMBASE, CINAHL, and LILACS using MeSH terms and keywords. Results will be limited to infants or children (ages >28 days to 12 years) hospitalized in LMICs and publications in English, Spanish, or French. Publications with non-original data (e.g., comments, editorials, letters, notes, conference materials) will be excluded.Study SelectionWe will include observational studies published since January 1, 2005, that meet all eligibility criteria and for which a full text can be located.Data ExtractionData extraction will include information related to study characteristics, hospital characteristics, underlying population characteristics, patient population characteristics, and outcomes.Data SynthesisWe will extract and report data on study, hospital, and patient characteristics; outcomes; and risk of bias. We will report the causes of admission and mortality by region, country income level, and age. We will report or calculate the case fatality rate (CFR) for each diagnosis when data allow.ConclusionsBy understanding the burden of pediatric critical illness in LMICs, we can advocate for resources and inform resource allocation and investment decisions to improve the management and outcomes of children with acute pediatric critical illness in LMICs.

Malaria resulted in an estimated 627,000 deaths in 2020, the majority of which occurred in children under 5 years of age. Cerebral malaria (CM) is a severe manifestation of the disease with case fatality rates of up to 40%. Autopsies in children with CM have demonstrated sequestration of Plasmodium falciparum parasites in the brain as well as multiple other organs. Thus, multiple organ dysfunction syndrome (MODS) may be present in pediatric patients with CM, but its frequency and association with mortality have not been evaluated. This is a retrospective study of data collected prospectively from children with CM admitted in Blantyre, Malawi. Physical examination findings and laboratory values necessary to calculate a Pediatric Logistic Organ Dysfunction–2 (PELOD-2) score, a validated method that quantifies organ dysfunction in critically ill children, were abstracted. A total of 145 patients were included. Mortality was 15% (n = 22). Ten patients (7%) had single organ dysfunction, 36 (25%) had two organs involved, 68 (47%) had dysfunction of three organs, and 31 (21%) patients had four organs affected. Beyond neurologic dysfunction, other organ systems involved included hematologic (77%), renal (61%), cardiovascular (44%), and respiratory (1%). The median PELOD-2 score on admission was 4 (range: 3–6) in survivors and 6.5 (range: 5–10) in the nonsurvivors (P < 0.0001). Admission PELOD-2 score predicted mortality with an area under the curve of 0.75. MODS is widespread in pediatric patients with CM. Objectively identifying children with MODS, and therefore at an increased risk of mortality, may allow for the allocation of limited resources.